1. Field of the Invention
The present invention relates to an air bag apparatus in which an air bag module, including an inflator and a folded air bag, are contained in a case comprised of a main body and a cover. The main body can have a square shape and a pair of coupling bars to integrate and hold the cover member to the main body.
The air bag is applicable to use with passengers, for a steering wheel, for a side door, for a seat back or at other desirable locations in an automobile.
2. Description of Related Art
A conventional air bag apparatus, for example, includes an air bag module with an inflator and an air bag is integrally contained in a case, with the case being constituted to integrally couple together a cover member and a case.
Further, normally when integrally coupling the main body and the cover member, leg portions formed on a lower face of the cover member are brought into contact with outer side faces of the main body, and are fastened together by rivets at a plurality of portions. Riveting is carried out mainly for the reason of strength.
However, when riveting a number of separate parts (rivets, rivet seats and so on) are needed, and a number of steps of riveting are required.
3. Summary of the Invention
It is an object of the invention to provide an air bag apparatus capable of eliminating rivets when a cover member is fixedly coupled to a main body of a case to enclose an air bag module.
According to an aspect of the invention, there is provided an air bag apparatus having a configuration in which an air bag module substantially including an inflator and an air bag is integrally contained in a case, and the case includes a cover member, a main body, and a pair of coupling bars for coupling the cover member to the main body.
The cover member includes attaching leg portions, having a wall-like shape, fitted to outer sides of the main body at a lower face of the cover member on at least two sides thereof, and the attaching leg portions each includes a plurality of engaging holes.
The main body includes a plurality of engaging projections corresponding with the engaging holes at side walls of the main body. Each of the engaging projections includes a lock hole opened at least to a lower side, and disposed on an outer side of the attaching leg portion of the cover member when the engaging projection is fitted to the engaging hole.
The coupling bar includes a fixed seat portion having a plate-like shape and a plurality of lock pieces extending from the fixed seat portion in an upward direction and corresponding with the size and location of the lock holes.
The fixed seat portions of the coupling bars are brought into contact with the main body, and fixedly fastened together along with the air bag. The lock pieces are inserted from a lower side into the lock holes of the engaging projections by which the attaching leg portions of the cover member are fixedly coupled to both side walls of the main body.
In the above-described configuration, it is preferable that the lock holes be of a penetration type, and that the lock pieces be provided with a length projected to the upper side of the lock holes. It is also preferable that the lock pieces be provided with a length overlapping an upper edge of the engaging holes of the cover member.
Further, the lock pieces can be constituted to provide a stopper piece that is locked to the engaging hole of the cover member on a lower side thereof.
By the above-described configuration, in coupling the cover member with the main body, the coupling bars which are fixed by using both retainers and fastening bolts are utilized; accordingly, in connecting the cover member with the main body, rivets can be eliminated. In comparison with the conventional case in which the cover member and the main body are coupled by the rivets, the number of parts (rivets and rivet seats) required is reduced. Further, the riveting operation, requiring a number of steps, is dispensed with, thereby further reducing the number of manufacturing steps.